1. Field of the Invention
This invention relates to towable submarines for scuba divers and particularly to towable submarines for divers that have partial enclosures for the diver.
2. Description of Related Art
Towable submarines for divers are devices that allow scuba divers to be towed through the water at high speeds. Today, most designs of diver tow systems are really flat platforms that a diver reclines upon while a surface vessel tows the platform. One use for such tow craft is surveying or searching the ocean floor. While the tow boat follows a predetermined search pattern on the surface, the diver can pilot the tow craft (or tow sub) over the bottom to search, without having to constantly swim.
An example of a typical tow sled is found in U.S. Pat. No. 3,931,777 to Colgan. This design has a flat platform, a towing ring, control surfaces and a tilted "windshield." Although this design works, it has several limitations. Because the diver has little protection, the sled can be towed only at low speeds (typically less than 2 knots). Also, the tilted windshield tends to cause turbulence in the area behind the windshield. This causes considerable discomfort for a diver, especially when the speed of the sled increases. Moreover, the backwash breaks up the diver's air bubbles and swirls them forward. This obscures the diver's vision, which not only undermines the purpose of the tow sled, but can also be dangerous for the diver.